Black Hole Spectrum, Horison Quantization and All That

TL;DR

This paper explores the idea that quantum black holes may have a discrete mass spectrum, examining theoretical arguments from string theory, lower-dimensional models, and horizon membrane models to support this hypothesis.

Contribution

It introduces the concept of discrete black hole spectra and discusses supporting theoretical arguments, including heterotic string theory and membrane models.

Findings

Quantum black holes may have discrete mass spectra.

Heterotic string theory suggests decoupling of sectors supports spectrum discreteness.

Lower-dimensional black hole models provide additional evidence.

Abstract

We discuss the possibility that quantum black holes have discrete mass spectrum. Different arguments leading to this conclusion are considered, particularly the decoupling between left and right sectors in string theory - the so-called heterotic principle. The case of a $2+1$ dimensional black holes is considered as an argument in favour of this argument. The possible connection between membrane model of the black hole horizon and topological membrane is briefly discussed.